Dispenser, mixer and feeder



March 19, 1968- A. PFEUFFER DISPENSER,

MIXER AND FEEDER Filed Jan. 17, 1966 INVENTOR. ANTON PFEUFFER ATTORNEYS United States Patent 3,373,901 DISPENSER, MIXER AND FEEDER Anton Pfeuffer, 301 E. 78th St., New York, N.Y. 10021 Filed Jan. 17, 1966, Ser. No. 521,132 3 Claims. (Cl. 222-57) ABSTRACT OF THE DISCLOSURE An even flow-rate device is coupled to a hopper for eifecting even flow-rate of bulky material passing therethrough. The even flow-rate device comprises a first perforated member disposed adjacent the hopper and having a predetermined number of openings therethrough. A dispenser is coupled to the even flow-rate device for dispensing the bulky material to a mixing chamber. The even flow-rate device comprises a second perforated member disposed adjacent the dispenser and having a predetermined number of openings therethrough. The openings in the first and second perforated members are conically shaped to form a smaller and a larger opening at the opposite faces of the perforated members and cutting edges are formed around the smaller openings of the first and second perforated members.

The present invention relates generally to an apparatus for supplying dry solids to liquids, and more particularly relates to an apparatus providing accurate and continuous mixing and feeding of dry solids to liquids. Moreover, this invention relates to an improvement to the apparatus described in my US. Patent No. 3,039,655, issued June 19, 1962 and to the apparatus described in my co-pending application Ser. No. 435,540, filed Feb. 26, 1965.

The apparatus of my aforementioned patent and the one described in my co-pending application solve a problem in which measured amounts of a filter-aid material such as infusorial earth are added to a fluid flowing in a pipeline and carried along the pipeline to a filter. More particularly, the prior described apparatus rely on the principle that an increase in the eifective surface area of any given feed or supply device will result in an increase in the devices capability of supplying filter-aid to a filtration system.

To this effect, my prior apparatus provides in one particular embodiment of that prior invention, a plurality of cylindrical containers, each containing a quantity of infusorial earth or the like, such cylindrical containers terminating at a funnel-shaped base portion of the feed device, the cylindrical containers having associated therewith washdown funnels located at the lower end of the cylinders, whereby an uninterrupted movement of the dry solids is attained.

In the above-mentioned prior apparatus, it is a basic requirement that a gaseous medium or liquid medium should be introduced at different portions of an associated hopper so that bridging of the dry solids could be prevented.

An object of the present invention is to provide an improved continuous feeding device not requiring prior mixing of the dry solids with gaseous medium.

It is a further object of the present invention to provide an apparatus for continuous mixing and feeding of dry Patented Mar. 19,1968

solids to liquids, wherein an accurate metering of the supplied solids is attained.

A still further object of the invention is to provide an improved continuous mixing and feeding device, wherein a metering device is interposed between the hopper and the mixing chamber of the apparatus, such metering device being interchangeable in accordance with the particular requirement of the flow rate of solids to the mixing chamber.

In accordance with the invention, the mixing apparatus comprises a hopper, a mixing chamber coupled to the line in which the liquid flows, and a device for effecting controlled even flow of solids interchangeably disposed between the hopper and the mixing chamber and separated therefrom by perforated plates, such perforated plates being removably attached between the hopper and the metering device as Well as between the metering device and the mixing chamber, and a motor driven shaft having stirrers associated therewith extending through the hopper into the metering device, preferably each plate having a stirrer associated therewith.

The invention will become more readily apparent from the following description of a preferred embodiment thereof shown, by way of example, in the accompanying drawings, in which:

FIG. 1 is a side view of the apparatus in accordance with the invention, partly in section;

FIG. 2 is an elevational view of an in-line type pressurized feeder in accordance with the invention; and

FIG. 3 is an elevational view of a rotary pump type feeder in accordance with the invention.

With particular reference to FIG. 1, the mixing apparatus is designated generally by 10, includes a hopper 11, into which the dry solids such as pulverized, granular, floodable, free flowing or non-free flowing types are fed either directly or by pneumatic means, not shown, from a distant supply tank. The hopper is provided preferably with a tapering funnel portion 11a which terminates into a cylindrical throat portion 11b which has a flange portion 22 integrally formed therewith to secure the hopper of the apparatus to the remaining parts thereof. A gear motor 24 is disposed above the hopper and drives a shaft 12 at a predetermined rate. Shaft 12 has a stirrer 13 attached thereto, such stirrer being disposed at the bottom portion of the hopper at a level where the tapered portion thereof terminates. At the termination of cylindrical throat portion, shaft 12 has a second stirrer 14 attached thereto. Flange portion 22 cooperates with a flange portion 23 of a metering device 16 which is so disposed with respect to the throat portion 11b of the apparatus that a substantially cylindrical continuous passageway is formed between throat portion 11b and the metering device. Between throat portion 11b and the metering device 16 a perforated plate 15 is disposed and held in position by flange portions 22 and 23. The perforated plate 15 is so designedthat its openings may amount to 10 to of the total area thereof. The openings in the perforated plate are conically shaped and the plate is inserted into the apparatus so that the smaller opening of the conically shaped openings face toward the hopper and are formed with sharp cutting edges. The metering device is attached to the hopper preferably by clamps which are easily removable and permit easy and quick interchange of the perforated plate in accordance with the requirement of a particular flow-rate associated with a particular type of dry solid being used. With respect to the clamping arrangement, reference may be had to my application Ser. No. 518,151, filed Ian. 3, 1966. The hopper and the metering device are preferably made from plastic, cast iron, copper, brass or stainless steel. The perforated plate is preferably made from an abrasive-resistant material such as polished steel, stainless steel, nylon or Teflon. In a preferred embodiment of the invention, the metering device 16 is provided with transparent cylindrical walls 16a which form windows in a supporting frame 16b. Stirrer 14, in the embodiment shown, is disposed closely adjacent to the perforated plate 15 so that as soon as the apparatus is started up, the stirrer associated with the particular plate, pushes a certain amount of material over the cutting edges of the openings so that the material finds its way below into the metering device. The metering device at the bottom portion thereof, has a flange 24 formed which cooperates with a flange 25 of a mixing chamber 19 which similarly as metering device 16 may be formed with plastic walls 19a forming windows in a supporting frame 19b. A further perforated plate 18 is disposed between metering device 16 and the mixing chamber 19, and is similarly attached between flanges 24, 25 like perforated plate 15 between flanges 22 and 23, in other words, in a removable and interchangeable fashion. Perforated plate 18 has also a predetermined number of openings formed therein, which are conically shaped and the plate is inserted into the device so that the smaller side of the tapered openings face upwardly, toward the metering device, and have cutting edges formed at their smaller openings. Adjacent the perforated plate 18, there is disposed another stirrer 17, closely adjacent with the perforated plate 18. Stirrer 17 is attached to shaft 12 which extends through metering device and is terminated preferably with the stirrer 17. Stirrer 17 may be in the form of an L-shaped member. The openings in perforated plates 15 and 18 of a particular set are correlated with each other and with the rate of rotation of shaft 12, so that any level of the dry solids in the hopper will result in an even flow of such dry solids to the mixing chamber. For example, a smaller percentage of the openings in perforated plate 15 and a large percentage of openings in the bottom plate 18 for a particular requirement will result, at a predetermined rate of rotation of shaft 12, in even flow-rate of a given solid to the mixing chamber 19. The metering device is secured to the mixing chamber 19, also by clamps which facilitate easy and quick disassembly of the metering device from the mixing chamber or a quick interrhange of the respective perforated plates. Mixing chamber 19, in open type applications, may have an overflow portion having openings circumferentially therearound for permitting excessive material to leave through the openings. Such overflow portion is particularly useful in applications where the apparatus is used, for example, for feeding soap into a line.

In order to properly mix the dry solids with a fluid, the level of the fluid in the mixing chamber is maintained at a suflicient level. The fluid level within the chamber is controlled by regulating the amount of fluid passing through a valve 26 supplied from line 27. A larger volume of fluid in the chamber permits larger amounts of dry solids to be mixed with the fluid.

It may be desirable to provide further control of the fluid level in mixing chamber 1?. To this effect, an electromechanical fluid level control device 28 may be coupled to the mixing chamber at a level which represents the desired maximum or minimum liquid level. The fluid level control device 28 upon being actuated by the fluid reaching that level is adapted to control operation of the stirrer motor 24 through connection 29 and/or the operation of a pump, when the particular feeder apparatus operates with a pump, which delivers to hopper 11, through connection 30.

The fluid level control device 28 may be of a known type which operates through actuation of contacts upon being engaged by the fluid in the mixing chamber.

A differential pressure valve is preferably used for the closed type pressurized feeders to control the liquid level in the mixing chamber by sensing the pressure in line 27 upstream of the feeder and comparing the same with the counter pressure applied to the hopper. By decreasing or increasing the counter pressure, or adjusting the counter pressure to a predetermined value, by means of the differential pressure valve, the liquid level becomes accordingly regulated in the mixing chamber.

The inventive feeder apparatus may be connected into the line, as shown in the preferred embodiment of FIG. 1, by an eductor type connection, such arrangement may be referred to as the eductor type open feeder apparatus.

In industrial applications, a pressurized type in-line feeder apparatus may be more advantageous. Such apparatus may be referred to as a pressurized or closed feeder apparatus which is arranged in the line as shown in FIG. 2.

In other applications where it is necessary to overcome a pressure head in the filters, and where the apparatus is used to supply the solids as a filter aid to a filtration system, either a rotary pump type feeder which may employ a so-called Moyno-Purnp, or a diaphragm pump type feeder may be used with advantage. Such feeders may be of the open or closed type. A rotary pump feeder of the closed type is disclosed in FIG. 3. It is understood that an eductor may also be used with the closed type feeder system.

The advantages of the invention become particularly apparent when employed in industries encountering mixing, blending and filtering problems in connection with the treatment of soap, sugar, salt, and chemical products, which heretofore have been treated by expensive feeding systems using metering pumps responsive to the changes in the specific gravity of the slurry into which these materials are formed before their admixing into a fluid. It has been found that there is no simple way to keep a slurry at a constant specific gravity by conventional means. At the beginning of the mixing process, there will be always a lower specific gravity in a slurry, which affects the flow rate thereof, which in turn leads to an inconsistent admixing of the slurry to the liquid at different phases of the process.

As has been seen, the subject invention dispenses with the necessity of treating the solids with gaseous materials and the use of expensive metering apparatus by providing simple mechanical flow rate control arrangement. The practice of the invention permits the attainment of a constant flow rate of the solids to a mixing chamber.

The invention is capable of numerous forms and applications without departing from the essential features herein disclosed. It is, therefore, intended and desired that the embodiment shall herein be deemed illustrative and not restrictive and that the patent shall cover all patentable novelty herein set forth; reference should be had to the following claims rat-her than 'to the specific embodiments herein, to indicate the scope of this invention.

What I claim is:

1. A device for mixing a bulky pulverulent material and a fluid in a smooth and uninterrupted flow, comprising hopper means for initially containing the bulky material; driving means cooperating with the hopper means and including a rotatable shaft extending axially with respect to said hopper means, a mixing chamber disposed below said hopper means including a liquid inlet and a discharge; means for dispensing said bulky material to said mixing chamber; a plurality of perforated members disposed at selected elevations having holes formed therethrough; a plurality of stirrers disposed at different elevations secured to said rotatable shaft, at least one of said stirrers disposed adjacent one of said perforated mem bers; fluid level responsive means disposed in a portion of said mixing chamber below the lowermost of said stirrers and connected to said driving means for feeding a desired quantity of pulverulent material to said mixing chamber; and pump means responsive to said fluid level responsive means for controlling the flow of pulverulent material to said hopper means.

2. A device according to claim 1, wherein the holes in said perforated members are conically shaped to form cutting edges around the smaller diameters of said conical holes.

3. A device according to claim 1, wherein the holes in said perforated members comprise from about 10% to about 65% of the effective area of each respective perforated member.

References Cited UNITED STATES PATENTS 1,172,603 2/1916 Johnson. 1,679,557 8/ 1928 Bailey 222-56 2,358,208 9/ 1944 Braden 222240 2,723,780 11/ 1955 Clement 222239 FOREIGN PATENTS 913,671 12/1962 Great Britain. 931,117 7/1963 Great Britain.

ROBERT B. REEVES, Primary Examiner.

H. S. LANE, Examiner. 

